Trigger mechanism



Aug. 9 1938. H. c WRlGHT ET AL 2,126,076

TRIGGER MECHANISM Filed Aug. 3, 1956 INVENTORS H c. vvr gzw H WA lelvATTORNEY BY Qw ymdmzt:

Patented Aug. 9, 1938 UNITED STATES OFFICE TRIGGER MECHANISM For-tier,Fresno flalif.

Application August 3, 1936, Serial No. 93,956

V Claims. (01. 42-69) This inventionrelates generally to a triggermechanism for rifles and in particular is directed to a triggermechanism for use in connection with target rifles.

In the use of target rifles where great accuracy is vital, it isnecessary that the trigger mechanism be constructed so that the rifleembodying such mechanism may be fired with a minimum of movement orcreep" of the trigger, and preferably with little or no rebound of thetrigger when the firing pin is released and snaps forward. However, thetrigger mechanisms heretofore available have lacked the desiredsensitiveness of operation,

It is therefore the principal object of our invention to provide atrigger mechanism for target rifles which may be actuated with a minimumof creep", and with no rebound Further objects of our invention are toprovide a trigger mechanism which is so constructed that the point ofengagement of the sear with the trigger may be adjusted in order toassure a minimum of "creep, and to provide a trigger mechanism in whichthe sear and trigger may be disengaged with a trigger pull which is notonly uniform at all times, but which exerts very much smaller pressureagainst the sear than that exerted on the head of the tumbler by thespring pressed firing pin.

It is also our object to provide a trigger mechanism in which the weightof the pull of the trigger may be selectively adjusted, depending on therequirements of any particular rifle match.

A further object of the invention is to produce a simple and inexpensivedevice and yet one which will be exceedingly effective for the purposefor which it is designed.

These objects we accomplish by means of such structure and relativearrangement of parts as will fully appear by a perusal of the followingspecification and claims.

In the drawing similar characters of reference indicate correspondingparts in the several views:

Figure l is an enlarged side elevation of our improved trigger mechanismin cockedposition, and with one of the side plates removed.

Figure 2 is a similar view of the mechanism after the trigger has beenactuated and the rifle fired.

Referring now more particularly to the charactersof reference on thedrawing, our improved trigger mechanism comprises a pair of side plates,

one of which is indicated at I, rigidly connected together but spaced bymeans of relatively thin forward and rear spacing blocks 2.

A trigger 3 is pivoted at 4 between the side plates adjacent the rearspacing block 2 and depends from the pivot; the lower end of the triggerprojecting below the side plates in the form of a finger engaging member5 of usual 6 configuration.

An upwardly curving catch finger 6 is formed integral with the triggerand projects forwardly therefrom. A sear I is pivoted at 8 above andforwardly of the catch finger 6; said sear being 10 shaped so that onestraight edge of its extreme lower end will engage and rest on theopposite straight edge of the extreme upper end of catch finger B whenthe mechanism is cocked, as shown in Figure 1. Such point of engagementis hereit inaiter entitled the sear engaging point, and is indicated at9. The other opposed edges of the catch finger 6 and sear l are rounded,as at ill, to facilitate cocking of the mechanism.

A tumbler H of inverted T-shape is pivoted at its rear end at I!adjacent the pivot l of the trigger, and is adapted at its forward endto engage in a notch l3 cut in the adjacent edge of the sear Iimmediately below its pivot 8. The upper end of the tumbler is formedwith an enlarged head It having a straight rear edge; said edge engagingthe firing pin abutment l5, and holding the same in retracted positionwhen the trigger mechanism is cocked. The upper edge of head It isconcave to conform to the curvature of firing pin spring IS. The firingpin abutment i8 and spring it are of conventional construction, andtherefore are merely shown in dotted lines.

The sear I is provided with a curved rearwardly projecting cockingelement l'l, rounded at its end and overhanging a recessed portion IS inthe adjacent upper edge of the tumbler. A stop pin I9 is secured belowthe forward end of the tumbler to limit the extent of downward movementthereof. A relatively light tension spring is secured to and extendsbetween the lower edge of the tumbler and forward edge of the trigger.

A set screw 2| is threaded between the side plates in front of theforward edge of trigger 3, and serves as an adjustment for the searengaging point 8. A transverse binding screw 22 locks the screw 2|against accidental rotation.

Another set screw 23 having a light compression spring 2i disposed in abore therein and Pro jecting therefrom, is threaded between the sideplates on the other side of the trigger with the spring 24 engaging theadjacent edge of the trigger. This set screw serves as an adjustment forthe weight of'pull on the trigger required to trip adjustable stop forthe trigger when it is pulled. Machine screws 26 secure the side platestogether and retain the spacing blocks in place.

The trigger mechanism above described is mounted in a rifle in thefollowing manner:

The mechanism is slipped into the receiver of the rifle, and is securedin place by a pivot pin 21. In such position, a ledge 28 on the upperedge of the side plates at the rear abuts with a fixed portion of thereceiver, while the forward upper edges'of the side plates ahead ofpivot 27 are spaced from the adjacent portion of the receiver, as at 29.A compression spring 30 extends between said spaced parts, and exerts adownward pressure on the forward portion oi the trigger mechanism, whichbeing pivoted at 21 is thereby firmly held in the receiver rearwardly ofsaid pivot. In such position, the head it of tumbler ii is close to thefiring pin it as shown.

In use, our improved trigger operates as follows:

With the mechanism in cocked position, as shown in Fig. l, the catchfinger 6 is engaged with sear l; the amount of engagement at the searengaging point 9 being approximately .003. In such position, the searholds the forward end of the tumbler, which is engaged in notch it,raised from stop pin i9. With the parts cocked in such position, head Itof the tumbler cannot move forward, and as a result, the firing pinabutment i5 cannot move forward from its retracted position.

However, when the trigger is pulled or squeezed rearwardly aninfinitesimal amount, the sear engaging point 9 is broken, allowing searl to drop which instantaneously releases the forward end of the tumblerll from notch It in the sear. This results in the tumbler movingdownward about its pivot i2 until it engages stop pin it, causing head Mto move forward and downward just enough to permit the firing pinabutment to clear the head and be sprung forward under the force ofspring l5. When the firing pin is thus sprung forward, the cartridge inthe rifle is of course fired.

Due to the fact that the movement of the trigger to release themechanism is practically .imperceptible, there can be no undesirable"creep",

' and this, in combination with the fact that there is no connectionbetween the trigger and remaining mechanism after the sear engagingpoint 9 is broken, provides a trigger which has no rebound.

To cook the trigger mechanism, the rifie bolt is retracted by hand, andas the retracting abutment slips over head It, the head is drawnrearward, moving the tumbler up and about its pivot. When this occurs,cocking element ll of the sear engages in recessed portion I! of thetumbler. which results in curved faces ill of the rear and trigger beingbrought into engagement, and sliding past each other (the trigger givingway rearwardly) until the sear engaging point 9 is again 7 of the catchfinger in anaaove edge of head it. The mechanism is thus cocked andready for another filing operation.

Since the tumbler engaging catch notch it in the sear is close to thesear pivot 8, while the engaging point 9 of the sear-.ls a relativelygreat distance from the pivot s, the pressure at point 9 iscorrespondingly reduced from that exerted at notch l3 by the tumbler. Asa result, a very small pressure is sufilcient to hold the sear in cockedposition, and also only a very small trigger pressure is necessary torelease this hold.

. This of course means that the pressure of spring 2t may be very light.Besides giving a very sensitive trigger action, this tends to reducewear at the point 9 (both of the sear and trigger) to a minimum, so thatsaid points will remain in proper sharp edge form indefinitely,permitting the overlap at point 9 to be exceedingly small.

Due to the fact that the entire trigger mechanism is pivoted at 25 inthe receiver, and in view of the fact that the forward upper edges ofthe side plates are spaced from the receiver as at 39, the mechanism maybe swung so as to bring adjusting screws 2| and 23 to a position out ofthe receiver sufiiciently to reach the same and adjust either the searengaging point or weight of trigger pull.

From the foregoing description it will be readily seen that we haveproduced such a device as substantially fulfills the objects of theinvention as set forth herein. 7

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice such deviations from suchdetail may be resorted to as do not forma departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described our invention, what we claim as new and useful anddesire to secure by Letters Patent is:

1. In a trigger mechanism, a trigger pivoted at its upper end anddepending therefrom, a catch finger projecting forwardly from thetrigger intermediate its ends, the upper edge of the catch fingeradjacent the outer end thereof being inclined upwardly, a depending searpivoted ahead of the trigger and above the catch finger, the forwardedge of the sear adjacent its extreme lower end being arranged forslight .engagement with the extreme outer end of said inclined edge ofthe catch finger in fiat face to face relation whereby to limit forwardswinging movement of the sear, a firing pin control tumbler pivotedbetween the trigger and sear, and catch means between the tumbler andrear edge of the sear releasable upon separation of the sear and triggercatch finger and forward of the sear.

'2. In a trigger mechanism, a trigger pivoted at its upper end anddepending therefrom, a catch finger projecting forwardly from thetrigger intermediate its ends, the upper edge of the catch fingeradjacent the outer end thereof being inclined upwardly, a depending searpivoted ahead of the trigger and above the catch finger, the forwardedge of the sear adjacent its extreme lower end being arranged forslight engagement with the extreme outer end of said inclined edge fiatface to face relation whereby to limit forward swinging movement of thesear, and an inverted T-shaped firing pin control tumbler disposedbetween the sear and trigger and pivoted. adjacent the rear end forswinging movement. the sear having a notch in its rear edge below thesear pivot, the f 75 end of the tumbler being arranged to engage in saidnotch when the sear and trigger catch finger are engaged and to dropfrom said notch upon separation of the sear and trigger catch finger andforward swinging movement 01' the seat.

3. A trigger mechanism as in claim 1 in which the sear engaging portionof the inclined edge 01 the trigger catch finger is disposedsubstantially tangent to the are described by the outer end of the catchfinger upon swinging movement of the trigger about its pivot.

4. A trigger mechanism as in claim 2 including a tension springconnected at one end to the trigger above the catch finger, andconnected at the other end to the lower edge of the tumbler a cockingelement on the sear above its pivot.

said cocking element overhanging the forward arm of the tumbler andarranged to be-engaged and lifted by the tumbler when the central leg.thereof is retracted after the trigger has been released, whereby toswing the sear rearwardly about its pivot and re-engage the sear andtrigger catch finger as well as the sear and tumbler.

HENRY c. WRIGHT. HERBERT w. ALLEN.

